Packaging of cleaning products

Abstract: Cleaning products (e.g. soap tablets, powdered detergents) are packaged in a material which incorporates a fungicidally effective amount of a pyrithione derivative, preferably zinc pyrithione.

Description: The present invention relates to the packaging of cleaning products as well as to materials useful as packaging. Examples of cleaning products with which the invention is concerned includes personal care products such as tablets of soap as well as domestic cleaning products such as detergent formulations for laundering or dishwashing purposes. Various types of packaging are used for cleaning products. For example, soap tablets are wrapped in paper and as a further example detergent powders are packaged in cardboard boxes. As an additional example, liquid cleaning products (e.g. shampoos, dishwashing liquids) are sold in plastics containers. (The term packaging as used herein is also intended to cover such containers). It has long been recognised that the components present in cleaning products encourage mould growth in or on the packaging material. Thus for example soap tablets generally have a relatively high moisture content and also contain fatty acids. This combination of moisture and fatty acids (which are mould nutrients) can lead to mould growth on the paper in which the soap is wrapped. In order to avoid the problem of mould growth it has previously been proposed to incorporate a fungicide in the packaging material. One fungicide which has been used extensively for this purpose is Carbendazim. Carbendazim does however have a number of disadvantages. In particular, it is classified as a pesticide which places restriction on its use and moreover does not provide a sufficiently wide spectrum of activity to give total protection against mould growth. Another fungicide which has been used in packaging for cleaning products is TCMTB but this sensitises skin. JP900180462 discloses the use of pyrithione compounds in the treatment of paper for use in the construction of building boards. DE4122654 describes a composition containing a pyrithione compound used for the treatment of wood. It is therefore an object of the present invention to obviate or mitigate the abovementioned disadvantages. According to a first aspect of the present invention there is provided the combination of a cleaning product enclosed within packaging which incorporates a fungicidally effective amount of a pyrithione derivative, wherein the pyrithione derivative has a particle size of less than 10 microns. The cleaning product may for example be a solid product such as a tablet of soap (wrapped within packaging incorporating the pyrithione derivative) or a detergent powder in a box formed of a material incorporating the pyrithione derivative. Alternatively the cleaning product may be a liquid provided in a plastics container whereof the plastics material incorporates the pyrithione derivative. Pyrithione is a compound of the following structural formula Other names for pyrithione include: 2-mercaptopyridine-N-oxide 1-hydroxypyridine-2-thione 2-pyridinethiol-1-oxide 1-hydroxy-2(1H)-pyridinethione Pyrithione derivatives are used in a variety of personal care and cosmetic applications. Thus pyrithione derivatives are used as anti-dandruff agents m shampoos. As such, they are recognised as being non-harmful to human beings and therefore their use (as fungicidal agents in packaging for cleaning products) is fully acceptable. The pyrithione derivative is preferably incorporated in the packing material in the form of particles having a size of less than 5 microns. Preferably the packaging material comprises 250-2000 ppm of the pyrithione derivative. The pyrithione derivative may be incorporated in the base material of the packaging either during or after its production. The pyrithione derivative used in the invention is most preferably an insoluble derivative so as not to be "washed" off the packaging of the packaged cleaning product if the product is stored under conditions in which condensation is generated. The preferred pyrithione derivative for use in the invention is zinc pyrithione which is of the formula: This compound is available from Olin Corporation under the trade mark Zinc Omadine. One example of packaging material is a non-woven cellulosic product, e.g. paper, cardboard or the like (such materials are particularly suitable for the packaging of solid cleaning products, e.g. soap tablets, powdered detergents). The pyrithione may be incorporated in the suspension of cellulose fibres from which the paper (or the like) web is formed. Alternatively the pyrithione derivative may be applied after formation of the web, e.g. by incorporating the pyrithione derivative in a solution (e.g. a thin starch solution) to be applied to the web at a size press, coating station or callender box. The invention will be illustrated by the following non-limiting Example. Example Two identical samples of paper were taken and one was treated with 750 ppm Zinc Omadine, the other being untreated to serve as a control. The paper samples were then placed on nutrient agar, sprayed with a mixed fungal suspension, and observed over a period of six weeks for fungal growth. The untreated paper was found to be completely overgrown by fungus after 1 week whereas there was no fungal growth on the paper treated with Zinc Omadine even after six weeks. Zinc Omadine treated paper is therefore eminently suitable for use in wrapping soap tablets.

Claims: A solid cleaning product enclosed within packaging which incorporates a fungicidally effective amount of a pyrithione derivative, wherein the pyrithione derivative has a particle size of less than 10 microns. The combination as claimed in claim 1 wherein the pyrithione derivative is an insoluble derivative. The combination as claimed in claim 1 wherein the pyrithione derivative is zinc pyrithione. The combination as claimed in any one of claims 1 to 3 wherein the pyrithione derivative has a particle size of less than 5 microns. The combination as claimed in any one of claims 1 to 4 wherein the packaging material comprises 250-2000 ppm of the pyrithione derivative. The combination as claimed in any one of claims 1 to 5 wherein the packaging material is a non-woven cellulosic product. The combination as claimed in any one of claims 1 to 6 wherein the cleaning product is a tablet of soap. The combination as claimed in any one of claims 1 to 6 wherein the cleaning product is a powdered detergent.

Inventors: WOOD STEPHEN GRAHAM, WOOD, STEPHEN GRAHAM
Applicants: MORRIS GREENHALGH LIMITED
Application year: 1994
Main classification: B65D81
IPC codes: A01N25, D21H21, B65D81, A01N43